<template>
  <div class="com-container" ref="seller_ref">
    <div class="com-chart"></div>
  </div>
</template>

<script>
import { mapState } from 'vuex'
export default {
  data() {
    return {
      chartInstance: null,
      allData: null,
      currentPage: 1, // 当前显示的页数
      totalPage: 0, // 一共页数
      timerId: null
    }
  },

  created() {
    this.$socket.registerCallBack('sellerData', this.getData)
  },

  mounted() {
    this.initChart()
    this.$socket.send({
      action: 'getData',
      socketType: 'sellerData',
      chartName: 'seller',
      value: ''
    })
    window.addEventListener('resize', this.screenAdapter)
    this.screenAdapter()
  },
  computed: {
    ...mapState(['theme'])
  },
  watch: {
    theme() {
      console.log('主题切换了')
      this.chartInstance.dispose() // 销毁当前的图表
      this.initChart() // 重新以最新的主题名称初始化图表对象
      this.screenAdapter() // 完成屏幕的适配
      this.updateChart() // 更新图表的展示
    }
  },
  destroyed() {
    clearInterval(this.timerId)
    window.removeEventListener('resize', this.screenAdapter)
    this.$socket.unRegisterCallBack('sellerData')
  },

  methods: {
    initChart() {
      this.chartInstance = this.$echarts.init(this.$refs.seller_ref, this.theme)
      // 对图表初始化配置的控制
      const initOption = {
        // 标题
        title: {
          text: '▎商家销售统计',
          left: 20,
          top: 20
        },
        // 坐标轴位置
        grid: {
          top: '20%',
          left: '3%',
          right: '6%',
          bottom: '3%',
          containLabel: true // 距离包含坐标轴上的文字
        },
        xAxis: {
          type: 'value'
        },
        yAxis: {
          type: 'category'
        },
        tooltip: {
          // 背景
          trigger: 'axis',
          axisPointer: {
            type: 'line',
            z: 0,
            lineStyle: {
              color: '#2D3443'
            }
          }
        },
        series: [
          {
            type: 'bar',
            itemStyle: {
              // 柱颜色渐变
              color: new this.$echarts.graphic.LinearGradient(0, 0, 1, 0, [
                {
                  offset: 0,
                  color: '#5052EE'
                },
                {
                  offset: 1,
                  color: '#AB6EE5'
                }
              ])
            },
            label: {
              // 柱文字
              show: true,
              position: 'right',
              textStyle: {
                color: 'white'
              }
            }
          }
        ]
      }
      this.chartInstance.setOption(initOption)

      this.chartInstance.on('mouseover', () => {
        clearInterval(this.timerId)
      })
      this.chartInstance.on('mouseout', () => {
        this.startInterval()
      })
    },
    getData(res) {
      // 也可以利用Promise()拿到返回数据
      // this.$http.get("seller").then(response => {
      //   if (response.data) {
      //     console.log("sss");
      //   }
      // });

      // const { data: res } = await this.$http.get("seller");
      this.allData = res
      this.allData.sort((o1, o2) => {
        return o1.value - o2.value
      })

      // 每5个显示一页
      this.totalPage =
        this.allData.length % 5 === 0
          ? this.allData.length / 5
          : this.allData.length / 5 + 1
      this.updateChart()
      this.startInterval()
    },
    // 更新图表
    updateChart() {
      const start = (this.currentPage - 1) * 5
      const end = this.currentPage * 5
      const showData = this.allData.slice(start, end)

      // 处理数据并更新界面图表
      const sellerNames = showData.map((item) => {
        return item.name
      })
      const sellerValues = showData.map((item) => {
        return item.value
      })
      const dataOption = {
        yAxis: {
          data: sellerNames
        },
        series: [
          {
            data: sellerValues
          }
        ]
      }
      this.chartInstance.setOption(dataOption)
    },
    startInterval() {
      if (this.timerId) {
        clearInterval(this.timerId)
      }
      this.timerId = setInterval(() => {
        this.currentPage++
        if (this.currentPage > this.totalPage) {
          this.currentPage = 1
        }
        this.updateChart()
      }, 3000)
    },
    screenAdapter() {
      const titleFontSize = (this.$refs.seller_ref.offsetWidth / 100) * 3.6

      // 和分辨率大小有关的配置项
      const adapterOption = {
        title: {
          textStyle: {
            fontSize: titleFontSize
          }
        },
        tooltip: {
          axisPointer: {
            lineStyle: {
              width: titleFontSize
            }
          }
        },
        series: [
          {
            barWidth: titleFontSize,
            itemStyle: {
              barBorderRadius: [0, titleFontSize / 2, titleFontSize / 2, 0]
            }
          }
        ]
      }
      this.chartInstance.setOption(adapterOption)
      this.chartInstance.resize()
    }
  }
}
</script>
<style lang="less" scoped></style>
